"Heart-on-a-chip" could end drug testing on animals

The development of a “heart-on-a-chip” for testing new drugs could not only save time and billions of dollars in medical research, but also could end the use of animals in drug testing, according to researchers at the University of California, Berkeley.

As explained in the journal Scientific Reports, the scientists have developed a device populated with human heart cells that they believe could be an ideal tool for testing toxic side effects of new drugs on the human heart.

About one-third of drugs that are developed end up being discarded because of negative effects to the heart. To tackle this problem, the researchers created what they call a “cardiac microphysiological system (MPS),” that uses cells from human genes that are aligned to recreate the natural structure of human heart tissue to mimic blood flow. They say it can be used for biological, electrophysiological and physiological analysis.

By testing on this heart-chip model rather than animals, the researchers said that more accurate results of how drugs will interact with the heart can be understood, because animal hearts do not function exactly the same way as human hearts.

How was this heart-on-a-chip made? It was generated from human-induced pluripotent stem cells. It also has 3D geometry and spacing equivalent to that of human heart tissue. Different layers of heart cells were then added on, forcing the model to align in one direction. The model beats on its own at a normal rate of 55-80 beats per minute.

The team has tested four well-known cardiovascular drugs on the heart model and found that it responded as human hearts would to those medications.

The researchers say they will now look to see if they can create similar devices for other organs on a chip.

Breast, prostate cancers cluster in families

There’s more evidence suggesting that women are more likely to develop breast cancer in prostate cancer runs in their immediate family. Their findings from the Women’s Health Initiative reinforce suggest that since breast and prostate cancers tend to cluster in families, the two conditions share common genes.

More than 78,000 cancer-free women over the age of 50 were analyzed for the study, which began in 1993. The majority of the women participated for more than 10 years. At the start, women underwent a physical exam and detailed family and person histories were recorded. By 2009, 3,506 new breast cancer cases were diagnosed within the study group.

Of the participants, more than 11,000 had a mother, sister or daughter with breast cancer—this stat was more common for those who would eventually be diagnosed with the disease themselves—and 20 percent had a first-degree relative with breast cancer.

But more than 11 percent who went on to develop breast cancer had reported a first-degree relative with prostate cancer. Those with a father, brother or son with prostate cancer increased their risk of developing breast cancer by about 14 percent, according to the research. Compared to people who had no family history of either breast or prostate cancer, those who had a family history of both cancers were 80 percent more likely to develop breast cancer.

Researchers believe the possible link lies within the breast cancer genes BRCA1 and BRCA2 genes, which have been associated with prostate cancer as well.

Scientists find brain's pain center

One part of the brain is particularly active when we feel pain, according to researchers at the University of Oxford in the U.K., a finding, they say, could help doctors detect pain in people who can’t communicate well, such as small children or patients with dementia.

For the study, published in the journal Nature Neuroscience, 17 participants had capsaicin cream spread on their legs–that’s the compound in chili peppers that causes a burning sensation. The researchers then placed a hot or cold water bottle against each person’s skin to increase or decrease the pain.

While this was happening, the scientists scanned the participants’ brains. They also asked them to rate their pain levels. The scans indicated that when people reported feeling the most pain, an area deep in their brains called the dorsal posterior insula was particularly active. That, according to the scientists, suggests that this region of the brain acts as a kind of pain meter.

Next, the researchers hope to be able to determine if it’s possible to “turn off” this brain region in people with intractable pain.